1. Field of the Invention
This invention relates to the construction of electrical storage batteries relating to a welding apparatus for welding a battery terminal post to a battery bushing. More specifically, this invention relates to an improved resistive electrode for the welding apparatus having a superior heat distribution and a greater useful life.
2. Background of the Invention
The fabrication and assembly of an electric storage battery such as a lead acid storage battery have undergone major changes over the decades. The changes in the fabrication and assembly of an electric storage battery have been implemented to increase the reliability of the electric storage battery, to reduce the material cost of the electric storage battery and reduce the labor cost of associated with the assembly of the electric storage battery.
In some cases, many assembly process of the electric storage battery has been automated to reduce the overall cost of manufacture. One process in the assembly of the electric storage battery that has been automated is the process of electrically connecting a battery post to a battery bushing.
Typically, the battery case comprises a rectangular open top case having a plurality of intercell partition walls. A plurality of battery plates are respectively received between the plurality of intercell partition walls for forming a plurality of battery cell. The plurality of battery plates between the plurality of partition intercell walls are interconnected by intercell connectors extending through the intercell partition walls. The intercell connectors connect the plurality of battery plates between the plurality of partition intercell walls in an electrical series configuration.
A positive and negative battery post extends upwardly from the battery plates disposed in the battery cells at opposed ends of the battery case for providing a positive pole at one end of the battery case and a negative pole on the other end of the battery case. The positive and negative battery posts extend above the level of the battery case.
A battery case cover includes a positive and negative battery bushing secured to a top of the battery case cover. When the battery case cover is placed over the battery case, the positive and negative battery posts are received within the positive and negative bushings of the battery 4 case cover. The batter case cover is sealed to the battery case as should be well known to those skilled in the art.
The positive and negative battery post and the positive and negative battery bushings are made of a lead material in a lead acid battery. Various means have been devised in the past for electrically connecting the positive and negative battery posts to the positive and negative battery bushings secured to the battery case cover. One prior art method for electrically connecting the positive and negative battery posts to the positive and negative battery bushings is to utilize an open flame torch for melting the lead material to weld the positive and negative battery bushings to the positive and negative battery posts. Unfortunately, this prior art method provides inconsistent results and often produces electrical connections that appear to be satisfactory while being electrically defective. It should be appreciated by those skilled in the art that an improper or defect electrical connection between a battery post and a battery bushing is substantially detrimental to the overall performance of the electric storage battery.
In addition, the electrical connections of the positive and negative battery posts to the positive and negative battery bushings are essential to the safety of the electrical storage battery. If a battery post is not fused to the battery bushing, the electrical storage may leak acid and/or acid fumes from the battery bushing. There is also a hazard that the electric storage battery may explode causing damage to persona and/or property.
One novel method of electrically connecting the positive and negative battery posts to the positive and negative battery bushings utilizes an electrically conductive bushing mold and an electrically resistive electrode. The electrical conductive bushing mold was brought into engagement with the battery bushing and the resistive electrode was placed proximate the intersection of the battery bushing and the battery post. An electrical current was passed between the resistive electrode and the bushing mold for melting the battery bushing to provide the electrical connection between the battery post and the battery bushing. During the melting of the battery bushing, the resistive electrode was moved downwardly to ensure a substantial welding or bonding of the battery bushing and the battery post over desired vertical distance. The movement of the resistive electrode ensured that the battery bushing was properly electrically secured to the battery post.
Although the aforementioned prior art method provided electrical connections of superior reliability, this prior art process did have a major disadvantage. The major disadvantage of this prior art method was the requirement to frequently replace the resistive electrode. The need to frequently replacing the resistive electrode during the battery assembly process is a substantial disadvantage since the assembly process had to be halted in order to replace the resistive electrode in the welding process.
Therefore, it is an object of the present invention to provide an improved resistive electrode for welding a battery bushing to a battery post that overcomes the disadvantages of the prior art resistive electrodes and provides a substantial contribution to the battery assembly art.
Another object of this invention is to provide an improved resistive electrode for welding a battery bushing to a battery post with an increase useful life over the prior art resistive electrodes.
Another object of this invention is to provide an improved resistive electrode for welding a battery bushing to a battery post with a useful life of over six times the useful life of the resistive electrodes of the prior art.
Another object of this invention is to provide an improved resistive electrode for welding a battery bushing to a battery post incorporating a conductive sleeve for enhancing the flow of electrical current to a tip end of the resistive electrode for concentrating the resistive heat proximate to the tip end of the resistive electrode.
Another object of this invention is to provide an improved resistive electrode for welding a battery bushing to a battery post for facilitating the transfer of heat from the resistive electrode to a cooling fluid internal to the resistive electrode.
The foregoing has outlined some of the more pertinent objects of the present invention. These objects should be construed as being merely illustrative of some of the more prominent features and applications of the invention. Many other beneficial results can be obtained by applying the disclosed invention in a different manner or modifying the invention with in the scope of the invention. Accordingly other objects in a full understanding of the invention may be had by referring to the summary of the invention, the detailed description describing the preferred embodiment in addition to the scope of the invention defined by the claims taken in conjunction with the accompanying drawings.